Photo-switches (or photo-conductive switches) are known by which light input triggers activation of the switch to conduct current therethrough under an electric potential thereacross. However, coupling light into the switch while mitigating electric field issues remains problematic. Additionally for repetitive pulse applications, thermal management must also be considered. One example known method employs a fused silica waveguide coupled through an oil-filled gap to a silicon carbide wafer. However, this approach is limited by the dielectric field strength of insulating oil especially in very high electric field regions problems with electric field management at the interface.
For high voltage applications producing high electric field regions, there is a need for a photo-conductive switch package capable of coupling light into the photo-conductive material while mitigating electric field issues in high voltage applications, such as bulk failure of photo-switch material or surface flashover at the edges of the switch.